Add the Doxygen note to non-supported RTOS and Driver class.

drivers/USBCDC_ECM.h

@@ -42,6 +42,7 @@
  * \defgroup drivers_USBCDC_ECM USBCDC_ECM class
  * \ingroup drivers-public-api-usb
  * @{
+ * @note Bare metal profile: This class is not supported.
  */
 
 class USBCDC_ECM: public USBDevice {

rtos/ConditionVariable.h

@@ -90,6 +90,8 @@ struct Waiter;
  *
  * @note Synchronization level: Thread safe
  *
+ * @note Bare metal profile: This class is not supported.
+ *
  * Example:
  *
  * @code

rtos/Mail.h

@@ -59,6 +59,9 @@ namespace rtos {
  * Memory considerations: The mail data store and control structures are part of this class - they do not (themselves)
  * allocate memory on the heap, both for the Mbed OS and underlying RTOS objects (static or dynamic RTOS memory
  * pools are not being used).
+ *
+ * @note
+ * Bare metal profile: This class is not supported.
  */
 template<typename T, uint32_t queue_sz>
 class Mail : private mbed::NonCopyable<Mail<T, queue_sz> > {

rtos/MemoryPool.h

@@ -51,6 +51,9 @@ namespace rtos {
  @note
  Memory considerations: The memory pool data store and control structures will be created on current thread's stack,
  both for the mbed OS and underlying RTOS objects (static or dynamic RTOS memory pools are not being used).
+
+ @note
+ Bare metal profile: This class is not supported.
 */
 template<typename T, uint32_t pool_sz>
 class MemoryPool : private mbed::NonCopyable<MemoryPool<T, pool_sz> > {

rtos/Queue.h

@@ -58,6 +58,7 @@ namespace rtos {
  *       current thread's stack, both for the Mbed OS and underlying RTOS
  *       objects (static or dynamic RTOS memory pools are not being used).
  *
+ * @note Bare metal profile: This class is not supported.
  */
 template<typename T, uint32_t queue_sz>
 class Queue : private mbed::NonCopyable<Queue<T, queue_sz> > {

rtos/Thread.h

@@ -84,6 +84,9 @@ namespace rtos {
  * to give access to particular thread used overloaded constructor with `tz_module` as argument during thread creation.
  *
  * MBED_TZ_DEFAULT_ACCESS is target specific define, should be set in targets.json file for Cortex-M23/M33 devices.
+ *
+ * @note
+ * Bare metal profile: This class is not supported.
  */
 
 class Thread : private mbed::NonCopyable<Thread> {